Method of making and repairing printing rollers



Patented Dec. 10, 1929 UNITED STATES CLARENCE HAMER, on ILION, New YORK, ASSIGNOB T0 REMINGTON ARMS comrAnY,"

PATENT OFFICE I INC., A CORPORATION OF DELAWARE METHOD OF MAKING AND REPAIRING PRINTING ROLLERS No Drawing.

llhe object of this invention is to provide an improved process for the production of yield mg elastic rollers which will possess a uniform smooth and glazed surface free of indentations. Rollers of the character specified are particularly adapted for use in connection with printing operations and may be used for the purpose of applying ink to the surface of printing type members or they may be used as the transfer medium in an offsetdprinting process. A particular use which requires an'especially smooth surface on the roller 1s that of transferring stain from a pattern cylinder or plate to a metallic Per cent Glue 26 Water 29 Linseed oil -Q 5 Sugar 10 Zinc oxide i 2 Glycerine as; 28 Venice turpentine, '1-0z. to every 15 '1bof composition desired. i The above mentioned ingredients prepared in substantially the percentages named, the water being preferably hot, are mixed and the liquid is thoroughly agitated by any suitable means to insure the coalescence of the ingredients. The composition, while still in a liquid state is then poured into a mold provided with suitable end bearings and a water jacket. After the mold is filled it is given a rotational movement about its end bearings either vertically or horlzontally at approximately 300 R. P. M. for about one hour. lllhis eliminates to a great extent the air pockets or-bubbles that may have been formed while the liquid composition was being poured or agitated At thetermination of the for rotating the mold the com has partially congealed and period selected osition which seems plastic per plate is Application filed July 24, 1925. Serial No. 45,936

by reason of the reduction of its temperature is further cooled by circulating cooling wateraround and through the jacket sur-: rounding the mold. This step, however, is

not essential, the particular advantage of it being that it reduces the time necessary to manufacturesuch rollers. Where the time element is not a particularly important consideration this may be omitted, and if desired, the water jacket need not be provided.thus permitting the composition to cool off naturally due to the lower temperature-of the surrounding air.

During the cooling stage the composition will coagulate and form itself'into a substantially homogeneous jelly-like but firm mass, the form of course, depending upon the mold,

and while the composition best lends itself to the formation of a cylindrical roller, other forms. more or less irregular in cross-section, have been produced with equally as good results. Whenever the term roller is used in this specification and in the claims which follow, it is to be understood to include bodies having other suitable forms as well as the true cylindrical form. After the composition has been cooled the mass may be withdrawn from the mold.

Rollers made according to the present proci ess may, as already stated, be used for a variety of purposes, such as, for inking rollers to supply ink to type elements or as a transfer medium in offset printing processes. A particularuse of the roller which, it has been found, requires special care to obtain a smooth, unindented surface, is in connection with the production of wood graining effects.

In order that this use of the roller formed by underthis invention may he more readily be very stood. the graining process will now briefly explained.

In reproducing the grains of quartered oak, mahogany or any other woods having grain which it is desired to imitate an etched copformed byrneans of any of the processes well known in the art and a plate so prepared is coated with a stain in any. manner desired. After the plate has received a coat of stain a scraper or doctor blade is drawn across the surface so that all the During the process of surface stain will be wiped off leaving a deposit of stain in the depressions formed in the etched plate.

A roller such as the one formed according to the process and by use of the composition hereinbefore explained is rolled over the surface of the plate and this roller picks up the stain on the plate. The roller is subsequently rolled over the surface or portion of the article to be grained and if this is a metal surface it will have been previously painted or enameled with a suitable ground color. The stain previously picked up from the copper plate will thus be transferred from the-roller to the article to be grained and there will be effected a reproduction on the article of the markings on the etched plate. The reproduction on the article may be preserved indefimtely by lacquering or varnishing the surface and subsequently subjecting the article to heat treatments to harden the finish.

While the results obtained by the use of rollers mahufactured by the process hereinbefore explained are satisfactory to a certain degree it has been found in practical use that the quality of reproduction of wood grain to a great extent depends upon the natu re of the surface of the roller of the transferring instruments.

tions will be left upon the article to be grained and the lines which are intended to simulate the graining will be broken and irregular. raining the soft rollers are forced with considerable pressure upon the article to be marked and occasionally the,

edges of the article or perforations therein will result in cutting and otherwise destroying the surface of the roller so that in a rela- {sivelyshorttime the roller may become useess.

The surface of the roller should be perfectly smooth and preferably glazed in order to readily pick up the stain-on theetched plate and it has been discovered that by the application of steam directly upon the periphery of each roller which has been made b the process previously; explained the surfllce of the original roller will be changed from one having a comparatively dull finish to one having a glass-like uniform surface possessing all the desired characteristics.

carrying out this step of the process the roller may be held in a suitable frame either h vertically or horizontally, and moist steam is applied from the nozzle of a hose, the ressure and force being regulated by a suitab e valve. The heat from the steam attacks the composition, the-latter melting and filling up such irregularities and depressions as origihally existed. The nozzle is preferably shifted longitudinally and passed over the periphery of the roller the latter being slowly rotated so as to treat all the peripheral area in the same way the general effect being to change it mto a unlform regular surface and by some addition of the plastic composition and steam may be applied locally. This will cause the added material to weld or coalesce with the material of the roller filling up the indentation and producing a smooth surface.

Rollers which by reason of constant use have acquired a poor surface may be readily refinished by thoroughly cleansing the sur face and subsequently applying steam to the same. Thus, manufactured rollers may be used indefinitely, the cost of the refinishing process being comparatively slight in comparison with the cost of a new roller.

While it has been found that steam is particularly advantageous as the source of heat for the last step of the process, as above explained, due to the moisture which it supplies with the heat, other heating mediums may be employed and it is not intended to restrict the present invention to the use of steam.

It is also the desire not to be limited to the proportions of the plastic composition previously given since they may be altered and if desired some of the ingredients may be omitted and others added. It is only essential that the composition possess a low melting point and be capable of producing when subjected to the heated vapor treatment a surface possessing the desired characteristics.

, What I claim is:

1. The improved process for forming printing rollers comprising the use of a liquid composition capable of forming a yielding and elastic substance when solidified and ing the latter to decrease the number of air pockets or bubbles; cooling the composltion;

and then applying steam to the'periphery of the cooled roller whereby the composition will be partly melted to fill in the crevices or indentations appearing on the surface.

. 2. The improved process for forming printing rollers comprising the use of a liquid composition capable of forming a yielding and elastic substance when solidified and aving a relatively low melting point; placing the liquid composition in a mold; rotating the latter to decrease the number of air pockets or bubbles; coolin the composition to solidify it, and then applying moist steam to the periphery of the solidified roller whereby the composition will be partly melted to fill in the indentations present on the surface.

3. The improved process for making printing rollers comprising the use of a liquid composition capable of forminga yielding and elastic substance when solidified, placing the liquid composition in a mold of desired shape, rotating the mold about itsaxis to decrease the number of air pockets or bubbles; cooling the composition to solidify the mass, and then subjecting the surface of the roller to the heat from a jet of vapor having a temperature higher than that of the melting point of the composition.

4 The improved method of finishing or resurfacing members composed of a" composition having a relatively low melting point comprising the application of steam to the periphery of the members, the steam having a temperature higher than that of the melting point of the composition.

In witness whereof I have signed my name this 22d day of July, 1925.

CLARENCE HAMER.

5. The improved method of finishin or re- I surfacing members composed of a yielding elastic composition having a relatively low melting point comprising the application of moist steam to the periphery of the members, the moist steam havin a temperature higher than that of the melting point of the composition.

6. The'improved method of refinishing the indented surfaces of inking members composed of yielding and elastic composition having a relatively low melting point, comprising. the insertion of a suitable added piece of the same composition in the indentation in the surface, and applying locally a jet of steam whereby the composition will partly melt and coalesce to effect a smooth surface.

7 The improved process of refinishing the surface of yielding printing members comprising the application of a jet of moist steam to the surface, and effecting a relative movement between the jet of steam and the inking, member whereby the entire peripheral area will be similarly treated.

8. The process herein described of refinishing the surfaces of materials composed of a yielding and elastic composition, which consists in bringing the surface of the material into the range of steam of sufiicient heat to permit the material to melt at the surface and flow evenly over the exterior surface.

9. The process herein described of refinishing the surfaces of materials composed of a yielding and elastic composition which consists in bringing the surface of the material into the range of heated vapor of sufiicient temperature to permit the surface material to melt and flow evenly over the entire exterior surface.

10. A process of making printing rollers for the purpose described comprising, the use of a yielding and elastic composition having a low melting point, molding the composi- 

